1. Technical Field
The present disclosure relates to a fuel cell system.
2. Description of the Related Art
In fuel cell systems in which a hydrocarbon is used as a raw material gas, an exhaust gas that is discharged from a fuel cell stack and a reformer contains moisture. Recovery and reuse of this moisture by condensing is commonly carried out in fuel cell systems that are water self-sustaining (a state in which operation continues without receiving replenishment water from outside).
For example, in the fuel cell system of Japanese Unexamined Patent Application Publication No. 2013-73903, a water flow rate regulating unit, which is a water supply means that produces and supplies pure water to a reformer, is provided. This unit is provided with a condenser, a first water storage tank, a condensed water tank, and a pulse pump. Moisture in the exhaust gas from a fuel cell module is condensed by means of the condenser, this condensed water is accumulated in the first water storage tank, pure water obtained by the condensed water being additionally purified is accumulated in the condensed water tank, and thereafter the pure water is supplied to the reformer by means of the pulse pump.
Furthermore, a solid oxide-type fuel cell system of Japanese Unexamined Patent Application Publication No. 2010-277973 is provided with a circulation flow passage that circulates water between a hot water storage tank and a heat exchanger, and a heat-dissipating means that is arranged in the circulation flow passage. Also, by dissipating heat from circulated water by means of the heat-dissipating means, the heat exchange efficiency of the heat exchanger is increased, and the recovery of water vapor in the exhaust gas is increased.